Adding the clinical framing, because it changes how the question reads. It helps to ask what evidence would change your mind before you look at any. If nothing would, the discussion is not about evidence, and it is better to say so early than to spend nine posts discovering it.

If somebody has the primary source to hand I would rather cite it than paraphrase it.

lucas_SP_BR said:

If you are going to change something, change one thing and give it long enough to express itself.

There is a second half to this that has not been said yet. Start from the measurement rather than the conclusion. Almost every disagreement here turns out to be two people measuring different things and comparing the numbers anyway.

I would rather be corrected than agreed with, if it comes to it.

The figures, for anyone assembling their own picture. The boring version of this is the one that works, and the boring version is: measure a baseline, change one variable, wait, measure again under the same conditions. Nobody wants that answer and it is still the answer.

Following on from lucas_SP_BR — and this may be the naive question:

How would you tell the difference between that and the alternative explanation?

Moderator note: leaving this open. It is being argued well and the disagreement is the useful part. Tagging this one for the weekly digest.